* [PATCH net-next] nat: remove obsolete rcu_read_unlock call
@ 2012-09-20 13:52 Ulrich Weber
2012-09-20 14:14 ` Eric Dumazet
2012-09-21 10:14 ` Pablo Neira Ayuso
0 siblings, 2 replies; 8+ messages in thread
From: Ulrich Weber @ 2012-09-20 13:52 UTC (permalink / raw)
To: netfilter-devel
hlist walk in find_appropriate_src() is not protected anymore by rcu_read_lock(),
so rcu_read_unlock() is unnecessary if in_range() matches.
Signed-off-by: Ulrich Weber <ulrich.weber@sophos.com>
---
net/netfilter/nf_nat_core.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c
index 1816ad3..125d832 100644
--- a/net/netfilter/nf_nat_core.c
+++ b/net/netfilter/nf_nat_core.c
@@ -201,10 +201,8 @@ find_appropriate_src(struct net *net, u16 zone,
&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
result->dst = tuple->dst;
- if (in_range(l3proto, l4proto, result, range)) {
- rcu_read_unlock();
+ if (in_range(l3proto, l4proto, result, range))
return 1;
- }
}
}
return 0;
--
1.7.9.5
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH net-next] nat: remove obsolete rcu_read_unlock call
2012-09-20 13:52 [PATCH net-next] nat: remove obsolete rcu_read_unlock call Ulrich Weber
@ 2012-09-20 14:14 ` Eric Dumazet
2012-09-20 14:17 ` Ulrich Weber
` (2 more replies)
2012-09-21 10:14 ` Pablo Neira Ayuso
1 sibling, 3 replies; 8+ messages in thread
From: Eric Dumazet @ 2012-09-20 14:14 UTC (permalink / raw)
To: Ulrich Weber; +Cc: netfilter-devel, Stephen Hemminger
On Thu, 2012-09-20 at 15:52 +0200, Ulrich Weber wrote:
> hlist walk in find_appropriate_src() is not protected anymore by rcu_read_lock(),
> so rcu_read_unlock() is unnecessary if in_range() matches.
>
> Signed-off-by: Ulrich Weber <ulrich.weber@sophos.com>
> ---
> net/netfilter/nf_nat_core.c | 4 +---
> 1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c
> index 1816ad3..125d832 100644
> --- a/net/netfilter/nf_nat_core.c
> +++ b/net/netfilter/nf_nat_core.c
> @@ -201,10 +201,8 @@ find_appropriate_src(struct net *net, u16 zone,
> &ct->tuplehash[IP_CT_DIR_REPLY].tuple);
> result->dst = tuple->dst;
>
> - if (in_range(l3proto, l4proto, result, range)) {
> - rcu_read_unlock();
> + if (in_range(l3proto, l4proto, result, range))
> return 1;
> - }
> }
> }
> return 0;
This could explain the rcu_read_unlock() imbalance Stephen had (lockdep
splat with net-next)
How old is this bug ?
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH net-next] nat: remove obsolete rcu_read_unlock call
2012-09-20 14:14 ` Eric Dumazet
@ 2012-09-20 14:17 ` Ulrich Weber
2012-09-21 10:14 ` Pablo Neira Ayuso
2012-09-20 16:27 ` Stephen Hemminger
2012-09-21 17:08 ` Stephen Hemminger
2 siblings, 1 reply; 8+ messages in thread
From: Ulrich Weber @ 2012-09-20 14:17 UTC (permalink / raw)
To: Eric Dumazet; +Cc: netfilter-devel, Stephen Hemminger
On 09/20/2012 04:14 PM, Eric Dumazet wrote:
> This could explain the rcu_read_unlock() imbalance Stephen had
> (lockdep splat with net-next) How old is this bug ?
Bug was introduced with c7232c9979cba684c50b64c513c4a83c9aa70563
Cheers
Ulrich
--
Ulrich Weber | ulrich.weber@sophos.com | Senior Software Engineer
Astaro - a Sophos company | Amalienbadstr 41 | 76227 Karlsruhe | Germany
Phone +49-721-25516-0 | Fax –200 | www.astaro.com
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^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH net-next] nat: remove obsolete rcu_read_unlock call
2012-09-20 14:14 ` Eric Dumazet
2012-09-20 14:17 ` Ulrich Weber
@ 2012-09-20 16:27 ` Stephen Hemminger
2012-09-21 17:08 ` Stephen Hemminger
2 siblings, 0 replies; 8+ messages in thread
From: Stephen Hemminger @ 2012-09-20 16:27 UTC (permalink / raw)
To: Eric Dumazet; +Cc: Ulrich Weber, netfilter-devel
On Thu, 20 Sep 2012 16:14:45 +0200
Eric Dumazet <eric.dumazet@gmail.com> wrote:
> On Thu, 2012-09-20 at 15:52 +0200, Ulrich Weber wrote:
> > hlist walk in find_appropriate_src() is not protected anymore by rcu_read_lock(),
> > so rcu_read_unlock() is unnecessary if in_range() matches.
> >
> > Signed-off-by: Ulrich Weber <ulrich.weber@sophos.com>
> > ---
> > net/netfilter/nf_nat_core.c | 4 +---
> > 1 file changed, 1 insertion(+), 3 deletions(-)
> >
> > diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c
> > index 1816ad3..125d832 100644
> > --- a/net/netfilter/nf_nat_core.c
> > +++ b/net/netfilter/nf_nat_core.c
> > @@ -201,10 +201,8 @@ find_appropriate_src(struct net *net, u16 zone,
> > &ct->tuplehash[IP_CT_DIR_REPLY].tuple);
> > result->dst = tuple->dst;
> >
> > - if (in_range(l3proto, l4proto, result, range)) {
> > - rcu_read_unlock();
> > + if (in_range(l3proto, l4proto, result, range))
> > return 1;
> > - }
> > }
> > }
> > return 0;
>
>
> This could explain the rcu_read_unlock() imbalance Stephen had (lockdep
> splat with net-next)
>
>
> How old is this bug ?
>
>
>
Will validate the fix tomorrow when back home.
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH net-next] nat: remove obsolete rcu_read_unlock call
2012-09-20 13:52 [PATCH net-next] nat: remove obsolete rcu_read_unlock call Ulrich Weber
2012-09-20 14:14 ` Eric Dumazet
@ 2012-09-21 10:14 ` Pablo Neira Ayuso
1 sibling, 0 replies; 8+ messages in thread
From: Pablo Neira Ayuso @ 2012-09-21 10:14 UTC (permalink / raw)
To: Ulrich Weber; +Cc: netfilter-devel
On Thu, Sep 20, 2012 at 03:52:04PM +0200, Ulrich Weber wrote:
> hlist walk in find_appropriate_src() is not protected anymore by rcu_read_lock(),
> so rcu_read_unlock() is unnecessary if in_range() matches.
Applied, thanks Ulrich.
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH net-next] nat: remove obsolete rcu_read_unlock call
2012-09-20 14:17 ` Ulrich Weber
@ 2012-09-21 10:14 ` Pablo Neira Ayuso
0 siblings, 0 replies; 8+ messages in thread
From: Pablo Neira Ayuso @ 2012-09-21 10:14 UTC (permalink / raw)
To: Ulrich Weber; +Cc: Eric Dumazet, netfilter-devel, Stephen Hemminger
On Thu, Sep 20, 2012 at 04:17:25PM +0200, Ulrich Weber wrote:
> On 09/20/2012 04:14 PM, Eric Dumazet wrote:
> >This could explain the rcu_read_unlock() imbalance Stephen had
> >(lockdep splat with net-next) How old is this bug ?
>
> Bug was introduced with c7232c9979cba684c50b64c513c4a83c9aa70563
I've added this to the patch description, it's good for the record.
Thanks.
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH net-next] nat: remove obsolete rcu_read_unlock call
2012-09-20 14:14 ` Eric Dumazet
2012-09-20 14:17 ` Ulrich Weber
2012-09-20 16:27 ` Stephen Hemminger
@ 2012-09-21 17:08 ` Stephen Hemminger
2012-09-21 19:47 ` Pablo Neira Ayuso
2 siblings, 1 reply; 8+ messages in thread
From: Stephen Hemminger @ 2012-09-21 17:08 UTC (permalink / raw)
To: Eric Dumazet; +Cc: Ulrich Weber, netfilter-devel
On Thu, 20 Sep 2012 16:14:45 +0200
Eric Dumazet <eric.dumazet@gmail.com> wrote:
> On Thu, 2012-09-20 at 15:52 +0200, Ulrich Weber wrote:
> > hlist walk in find_appropriate_src() is not protected anymore by rcu_read_lock(),
> > so rcu_read_unlock() is unnecessary if in_range() matches.
> >
> > Signed-off-by: Ulrich Weber <ulrich.weber@sophos.com>
> > ---
> > net/netfilter/nf_nat_core.c | 4 +---
> > 1 file changed, 1 insertion(+), 3 deletions(-)
> >
> > diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c
> > index 1816ad3..125d832 100644
> > --- a/net/netfilter/nf_nat_core.c
> > +++ b/net/netfilter/nf_nat_core.c
> > @@ -201,10 +201,8 @@ find_appropriate_src(struct net *net, u16 zone,
> > &ct->tuplehash[IP_CT_DIR_REPLY].tuple);
> > result->dst = tuple->dst;
> >
> > - if (in_range(l3proto, l4proto, result, range)) {
> > - rcu_read_unlock();
> > + if (in_range(l3proto, l4proto, result, range))
> > return 1;
> > - }
> > }
> > }
> > return 0;
>
>
> This could explain the rcu_read_unlock() imbalance Stephen had (lockdep
> splat with net-next)
>
>
> How old is this bug ?
>
>
>
This fixes the lockdep splat I saw when staring KVM vm's with net-next and lockdep enabled
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH net-next] nat: remove obsolete rcu_read_unlock call
2012-09-21 17:08 ` Stephen Hemminger
@ 2012-09-21 19:47 ` Pablo Neira Ayuso
0 siblings, 0 replies; 8+ messages in thread
From: Pablo Neira Ayuso @ 2012-09-21 19:47 UTC (permalink / raw)
To: Stephen Hemminger; +Cc: Eric Dumazet, Ulrich Weber, netfilter-devel
On Fri, Sep 21, 2012 at 10:08:42AM -0700, Stephen Hemminger wrote:
> On Thu, 20 Sep 2012 16:14:45 +0200
> Eric Dumazet <eric.dumazet@gmail.com> wrote:
>
> > On Thu, 2012-09-20 at 15:52 +0200, Ulrich Weber wrote:
> > > hlist walk in find_appropriate_src() is not protected anymore by rcu_read_lock(),
> > > so rcu_read_unlock() is unnecessary if in_range() matches.
> > >
> > > Signed-off-by: Ulrich Weber <ulrich.weber@sophos.com>
> > > ---
> > > net/netfilter/nf_nat_core.c | 4 +---
> > > 1 file changed, 1 insertion(+), 3 deletions(-)
> > >
> > > diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c
> > > index 1816ad3..125d832 100644
> > > --- a/net/netfilter/nf_nat_core.c
> > > +++ b/net/netfilter/nf_nat_core.c
> > > @@ -201,10 +201,8 @@ find_appropriate_src(struct net *net, u16 zone,
> > > &ct->tuplehash[IP_CT_DIR_REPLY].tuple);
> > > result->dst = tuple->dst;
> > >
> > > - if (in_range(l3proto, l4proto, result, range)) {
> > > - rcu_read_unlock();
> > > + if (in_range(l3proto, l4proto, result, range))
> > > return 1;
> > > - }
> > > }
> > > }
> > > return 0;
> >
> >
> > This could explain the rcu_read_unlock() imbalance Stephen had (lockdep
> > splat with net-next)
> >
> >
> > How old is this bug ?
> >
> >
> >
>
> This fixes the lockdep splat I saw when staring KVM vm's with net-next and lockdep enabled
It's in my tree already.
I'll pass it to David asap. Thanks for the report.
^ permalink raw reply [flat|nested] 8+ messages in thread
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2012-09-20 13:52 [PATCH net-next] nat: remove obsolete rcu_read_unlock call Ulrich Weber
2012-09-20 14:14 ` Eric Dumazet
2012-09-20 14:17 ` Ulrich Weber
2012-09-21 10:14 ` Pablo Neira Ayuso
2012-09-20 16:27 ` Stephen Hemminger
2012-09-21 17:08 ` Stephen Hemminger
2012-09-21 19:47 ` Pablo Neira Ayuso
2012-09-21 10:14 ` Pablo Neira Ayuso
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